Discontinuation of antipsychotic drugs in schizophrenia patients is a major concern, since it results in relapse and re-hospitalizations. Non-adherence is strongly associated with negative-subjective response to antipsychotics, which is composed of the subjective experience of negative drug effects and attitude towards the treatment.

To investigate the elements of subjective experience and subjective attitude towards specific drug-related adverse effects, leading to a generally negative-subjective attitude towards antipsychotics.

Schizophrenia inpatients (n = 84) were administered a questionnaire measuring attitude and experience on eight subscales: weight gain, sedation, sexual anhedonia, extra-pyramidal syndrome, affective flattening, excessive sleep, diminished sociability and metabolic syndrome. DAI-30 was used to measure attitude towards drugs, and PANSS to assess psychopathology.

Weak correlation was found between subjective experience and attitude on most of the subscales. The only strong, albeit inverse, correlation between experience and attitude that was found was with regard to affective flattening, experienced by 37% of the sample, and it also predicted negative drug attitude as measured by the DAI-30, RR: 1.87 (95% CI: 1.06–3.3, df = 1, χ2 = 4.525, P < 0.05).

Negative attitude towards most adverse drug effects did not correlate with personal experience. Drug-related affective flattening should be evaluated routinely, since experiencing it may predict negative attitude towards drugs, potentially leading to poor compliance and relapse.